The plain-English version
A reusable piece of code that performs a task.
Why it matters
A clear responsibility makes a function easier to inspect and test.
Let’s make it click
isOverdue(task, today) returns whether an active task's due date is before today.
Vibe Bro’s heads-up
A function that calculates a result and also writes data has side effects that need separate attention.
The docs behind it
Documentation links checked .
Editorial review · October 28, 2026
Supported: Read the full explanation, examples, and pitfalls; no material factual error identified. References are supporting reading, not a sentence-by-sentence source concordance.